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International audience; Silicon carbide (SiC) is emerging rapidly in novel photonic applications thanks to its unique photonic properties facilitated by the advances of nanotechnologies such as nanofabrication and nanofilm transfer. This review paper will start with the introduction of exceptional optical properties of silicon carbide. Then, a key structure, i.e., silicon carbide on insulator stack (SiCOI), is discussed which lays solid fundament for tight light confinement and strong light-SiC interaction in high quality factor and low volume optical cavities. As examples, microring resonator, microdisk and photonic crystal cavities are summarized in terms of quality (Q) factor, volume and polytypes. A main challenge for SiC photonic application is complementary metal-oxide-semiconductor (CMOS) compatibility and low-loss material growth. The state-of-the-art SiC with different polytypes and growth methods are reviewed and a roadmap for the loss reduction is predicted for photonic applications. Combining the fact that SiC possesses many different color centers with the SiCOI platform, SiC is also deemed to be a very competitive platform for future quantum photonic integrated circuit applications. Its perspectives and potential impacts are included at the end of this review paper.

Doped layers are a determining factor for the performance of photovoltaic devices such as silicon heterojunction and thin film silicon solar cells. The material properties of doped hydrogenated amorphous/nanocrystalline silicon-oxide (a/nc-SiO X≥0 :H) films processed by plasma-enhanced chemical vapor deposition generally exhibit a tradeoff between optical and electrical performance. The optoelectrical properties are the result of different material phases in these heterogeneous films, such as hydrogenated amorphous silicon and silicon-oxide tissue, nanocrystalline silicon grains, their corresponding fractions and extent of doping. In this article, all the precursor gas flows are varied to achieve a wide range of doped a/nc-SiO X≥0 :H phases. A material phase diagram is introduced to clarify the complex interplay between processing conditions, dominant growth mechanisms, a/nc-SiO X≥0 :H phases, and the resulting optoelectrical properties. In addition, it is discussed that material properties are strongly dependent on the thickness of the films, as the mix of different material phases is not uniform along the growth direction.

Management thinking today, based in neoliberalism, gears economies, businesses, and whole societies toward constant material growth and achievement of wealth, defined as monetary or financial wealth. In terms of management learning, the dominance of the managerialist/capitalist ideology reinforces existing dominance structures that have long suppressed the voice—and values—of Indigenous peoples. Drawing from work by Indigenous scholars, we focus on the Indigenous wisdom which has the potential to offer a very different form of economy and different sets of managerial values that orient businesses and other institutions towards fostering relationship, responsibility, reciprocity and redistribution for shared wellbeing. Perspectives from Indigenous wisdom can push focus away from today’s neoliberalism and “(hu)man”-dominating-nature mindsets, evident in Western cultures, towards more holistically integrated approaches. In the aftermath of the Covid-19 pandemic, we argue for a pivot towards recognizing, collaborating with, integrating, and renewing management and business school mindsets by incorporating Indigenous wisdom to build a world in which all—including non-human beings—can flourish.

The study of nano-scale surface phenomena is essential in understanding the physical processes that aid in technologically relevant applications, such as catalysis, material growth, and failure nuc...

This article comprehensively presents the latest development of state-of-the-art research and development in ZnO-material based ultraviolet (UV) photodetectors (PDs). A special focus to address the device physical mechanism understanding using modeling studies is carried out. A detailed analysis of different methods for improving the existing device performance is also discussed. The superior features of dual ion beam sputtering (DIBS) as a material growth system in order to realize high-performance UV PDs is presented. Most importantly, this article outlines the approach for improving the existing device performance by both modeling and fabrication methods. From the advantageous blistering evolution in material and device processes, alloyed ZnO-based UV PDs till date are one of the most prospective reliable solutions for UV detection technology. This article can provide indispensable insights into the current scenario of UV PDs and spur new structure alongwith device designs to further enhance photodetection performance. Finally, the article is concluded with some perspectives and outlook on the future developments in this area.

Summary Chemical vapor deposition (CVD) is a promising approach for the controllable synthesis of two-dimensional (2D) materials. Many studies have demonstrated that the morphology and structure of 2D materials are highly dependent on growth substrates. Hence, the choice of growth substrates is essential to achieve the precise control of CVD growth. Noble metal substrates have attracted enormous interest owing to the high catalytic activity and rich surface morphology for 2D material growth. In this review, we introduce recent progress in noble metals as substrates for the controllable growth of 2D materials. The underlying growth mechanism and substrate designs of noble metals based on their unique features are thoroughly discussed. In the end, we outline the advantages and challenges of using noble metal substrates and prospect the possible approaches to extend the uses of noble metal substrates for 2D material growth and enhance the structural controllability of the grown materials., Graphical abstract, Materials science; Materials synthesis; Nanomaterials

This study aimed to determined the differences between learning with free inquiry strategies on science process skills and learning outcomes on the materials of growth and development at SMA and MA in Kembang Tanjong, Pidie Regency. Data was collected on 6 October to 10 November 2018. This study use a quantitative descriptive approach with a quasi-experimental research technique. The design in this study is a non-equivalent control group design. The collecting of data divided into two groups: the experimental group and the control group. The number of samples in this study were 50 students for the experimental class and 52 students for the control class. Hypothesis this study testing based on the SPSS program version 23.0 for windows of a significance level of 0.05 obtained results; the value of science process skills students 6,055> 1.98 (thitung> ttabel), the value of student learning outcomes of a significance level of 0.05 obtained sig value is 5.965> 1.98 (thitung> ttabel). Based on two variables measured show that the implementation of the inquiry strategy there are differences between the science process skills and student learning outcomes in the material growth and development in plants at SMA and MA Negeri KembangTanjong, Pidie Regency.

In aluminum smelting cells, ledges freeze on to cell walls from the cryolitic bath when the temperature drops below the bath liquidus point. Modern cell design and control cause a suitable ledge profile to form and be maintained, in order to protect the cell walls from corrosive liquids (molten salts and Al metal) and ensure efficient current distribution and cell heat balance. During cell operation, a significant ledge, freezing and melting does occur following heat balance changes due to batch operations. The ledge formation mechanism has been studied at the laboratory scale in our previous work. It shows a linkage between the rate and directional nature of ledge growth and its structure as affected through a superheat change. An open ledge structure can dominate the laboratory ledge material growth or melt it out quickly when the superheat either decreases or increases, respectively. This paper begins the investigation of industrial ledge samples, in terms of structure and composition, primarily to identify whether the same ledge formation mechanism exists in industrial cells. In this study, as expected, the industrial ledge shows more complexity than the laboratory ledge; the open structure is different compared to the laboratory ledge due to the inclusion of carbon dust, a large thermal gradient across the ledge, and sufficient aging of the ledge in the cell. The comparison between the laboratory ledge and the industrial ledge has provided insight into the ledge growth mechanism in aluminum smelting cells.

Critical perspectives on economic growth have laid bare the fragility of the assumed link between material growth and socio-ecological wellbeing. The appeal of economic growth, however, goes beyond the economic sphere. As a societal goal, growth is often mobilized to pre-empt and/or co-opt opposition around issues of social justice and redistribution. Not only does the constitution of growth as a collective goal serve to unite the internally fragmented sphere of the social and brush aside (class-based) distributional conflicts, but it also enables the distribution of material concessions to subordinate classes for eliciting their consent. The degrowth proposal should thus more broadly tackle the material and discoursive ways in which growth enables the reproduction of contemporary political-economic systems. This paper argues that the notion of growth functions as a powerful ideal that shapes state–society relationships and social-collective imaginations. It demonstrates this by discussing the making of state in Turkey through a Gramscian perspective, where the notion of economic growth is deeply imprinted in the broader practices of the state to legitimize its existence and dominates the social imaginary in a way that cannot be easily dismissed. Against this backdrop, the possibility of not only effectuating, but also imagining and desiring degrowth would call for a radical reconfiguration of state–society relationships. Within this context, the Kurdish Freedom Movement’s project of Democratic Economy emerges as an alternative, both to the nation-state paradigm and to the imperative of economic growth.

We report on the room-temperature wafer-bonded InGaP/GaAs//InGaAsP/InGaAs four-junction solar cell grown by all solid-source molecular beam epitaxy (MBE). The material growth and structure optimization of multi-junction solar cell were investigated. The effect of growth temperature on phosphide-related material of the solar cell was discussed. The lattice-matched InGaP/GaAs tandem cell on GaAs substrate and InGaAsP- or InGaAsP/InGaAs-tandem cell on InP substrate were grown separately by MBE. Room-temperature wafer bonding technique was used to integrate the subcells into multi-junction solar cells. The current limiting of multi-junction cells was analysed and the device structure of four-junction solar cell was optimized. The best wafer-bonded four-junction solar cell reached a conversion efficiency of 42% under concentration.

We investigated the growth and characterization of InGaN films with high In content up to 51.9% obtained by MBE MME-growth. Comparing the structural and optical properties of InGaN films grown using common growth method and MME technique, we could acquire the good quality of InGaN sample by MME-growth method with lower dislocation density, better composition uniformity and smoother surface. These experimental results suggest that MME has an enormous potential to promote the quality of high In-content InGaN materials and the development of InGaN-based devices. Besides, further study shows the process of MME growth, the parameters of material growth have opposite effects on the background carrier concentration and carrier mobility.

This letter reports on initial investigation results on the material quality and device suitability of a homo-epitaxial 3C-SiC growth process. Atomic force microscopy surface investigations revealed root-mean square surface roughness levels of 163.21 nm, which was shown to be caused by pits (35 μm width and 450 nm depth) with a density of 1.09 × 105 cm−2 which had formed during material growth. On wider scan areas, the formation of these were seen to be caused by step bunching, revealing the need for further epitaxial process improvement. X-ray diffraction showed good average crystalline qualities with a full width of half-maximum of 160 arcseconds for the 3C-SiC (002) being lower than for the 3C-on-Si material (210 arcseconds). The analysis of C–V curves then revealed similar interface-trapped charge levels for freestanding 3C-SiC, 3C-SiC on Si and 4H-SiC, with forming gas post-deposition annealed freestanding 3C-SiC devices showing D IT levels of 3.3 × 1011 cm−2 eV−1 at E C−E T = 0.2 eV. The homo-epitaxially grown 3C-SiC material’s suitability for MOS applications could also be confirmed by leakage current measurements.

The purpose of this study is to see an increase in learning outcomes in the material growth and development in class VIII Junior High School Number 17 Palembang. This research is a quantitative research using quasi-experimental method design (Quasi Experimental). The design of this study used a preliminary test design and a final test. Based on the average value of the final class test using the Guided Inquiry learning model that is 76.90 is greater than the average value of the class using the lecture method that is 63.70. Then the analysis of the results of the t test calculation is obtained (t-count 6.777 while df (free degree) is 57.983, the significance is 0.000. So 6.777> 1.671 means Ha is accepted because the t-value is greater than the t-table value. And the probability is smaller than 0.05 values the significance is 0.05. So it can be concluded that learning using the Guided Inquiry learning model there is an increase in learning outcomes in the growth and development material of VIII grade students of Junior High School Number 17 Palembang.

Marshall decided to dedicate his life and career to economic studies because of the increasing urgency of the problem of poverty and of the so-called Residuum. This explains why, for him, the most important goal was to find the ways and the means to economic, social and human progress, which he clearly distinguished from material growth. Accordingly, Marshall developed a compound concept of “wellbeing” in which “wealth” was important and necessary but other aspects played a much more important role for the development of human faculties and (evolutionary) progress. The main aim of this chapter is to inquire into the concept of wellbeing and the complex nature of economic progress as conceived and dealt with by Marshall, particularly in his late notes for his unpublished book on economic progress.

The talk reviews progress on high-speed InGaAs/InP photodiodes on silicon-based photonic platforms. Recent results from heterogeneously integrated photodiodes based on adhesive die bonding and direct III-V material growth on Si will be discussed.

High-speed high-power photodiodes are key components in microwave photonic applications including antenna remoting, generation of microwave signals, and analog optical links. With the rapid emergence of Si photonics, it is becoming increasing important to develop approaches to incorporate these photodiodes into a Si platform. For integration of III-V photodiodes on silicon, various integration approaches have been reported, including adhesive wafer bonding, direct molecular wafer bonding, and direct III-V material growth on Si. This paper will report the integration of InGaAs/InGaAsP/InP modified uni-traveling carrier photodiodes using each of these techniques. In addition, high-power Ge on Si photodiodes will be discussed.

Similar simulation protocols are expected to be able to be used in studies of growth mechanisms of other 2D materials. Certainly, there are still many challenges in the study of two-dimensional material growth mechanism. For example, relaxation of the surface structure at very high temperatures may prohibit the use of lattice model in KMC simulations.

Based on the first-principles calculations, the total energy and electronic structures of some new inverse Heusler-based ternary intermetallic compounds X2YZ (X = alkali metals: Li, Na, K, Rb; Y = Ag, Pd, Cu; Z = Sb, Te, As) have been investigated in detail. Our results reveal that most of them are stable in inverse Heusler structure and naturally exhibit band-inversion nature without the effect of spin–orbit coupling (SOC). That is to say, most of our studied compounds are newly designed topological semi-metals. We also study the effects of the uniform strain and the spin–orbit coupling on the band inversion. Moreover, for our predicted compounds, all of them have a negative formation energy, which makes them possible in material growth.

After the discovery of graphene, other two-dimensional (2D) layered crystals have attracted extensive attention because of their fundamental physical properties. Semiconducting 2D solids, such as transition metal dichalcogenides (TMDCs), has superior benefits in terms of the ultra-thin body, high mechanical strength, and thermal stability. Most importantly, a new material platform could overcome the performance of graphene with a sizable electronic gap. As expected, the materials have a variety of device applications. Atomically thin TMDC layer preparation and assembly have been combined for generating a van der Waals layered material due to lack of robust techniques for epitaxial growth. In spite of significant research efforts on material growth, large-scale growth with defect-free film quality remains a challenge. Here, we provide an overview of the traditional approach and recent progress in top-down methods such as vapor phase growth and solution processes. Layer-by-layer stacking of diverse material toward the realization of complex heterostructured devices is discussed. State-of-the-art assembling techniques with alternative methods are described.

Nanostructured materials (NMs) are the materials with a microscopic structure of 1–100 nanometers. NMs can outperform their bulk counterparts, due to their reduced sizes. In terms of dimensionality, NMs can be classified into zero-dimension (0D), 1D, 2D, and 3D. Atomic and molecular layer deposition (i.e., ALD and MLD) are two unique techniques for fabricating and designing novel NMs, featuring their unique capabilities for material growth with excellent uniformity, unrivaled conformal coverage, and precise controllability at low temperature. As a result, a large variety of NMs by ALD and MLD have found applications in a wide range of areas. In this work, we focus on summarizing the strategies of ALD and MLD for various NMs and exemplify their applications in surface engineering and new energies.

There are broad interests in selective and localized synthesis in nanodomains of self-assembled block copolymers (BCPs) for a variety of applications. Sequential infiltration synthesis (SIS) shows promise to selectively grow a controllable amount of materials in one type of nanodomain of a self-assembled BCP film. However, the effects of nanostructured domains in a BCP film and SIS cycles on the material growth behavior of SIS are rarely studied. In this work, we investigated the growth behavior of TiO2 SIS within self-assembled polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) films and the two corresponding pure homopolymer films (PS and PMMA) by using in situ quartz crystal microbalance (QCM). According to the experimental results, reactant purge steps are essential to enable a high selectivity of SIS in PMMA nanodomains in the BCP films by eliminating the undesired homogeneous reactions. The continuous PS nanodomain acts as the main channel in transporting reactants to PMMA nanodomains in the se...

Cadmium telluride-based solar cell is the most successfully commercialised thin film solar cell today. The laboratory-scale small devices have achieved ~ 22%, and commercial solar panels have reached ~ 18% conversion efficiencies. However, there are various technical complications and some notable scientific contradictions that appear in the scientific literature published since the early 1970s. This review paper discusses some of these major complications and controversies in order to focus future research on issues of material growth and characterisation, post-growth processing, device architectures and interpretation of the results. Although CdTe can be grown using more than 14 different growth techniques, successful commercialisation has been taken place using close-space sublimation and electrodeposition techniques only. The experimental results presented in this review are mainly based on electrodeposition. Historical trends of research and commercial successes have also been discussed compared to the timeline of novel breakthroughs in this field. Deeper understanding of these issues may lead to further increase in conversion efficiencies of this solar cell. Some novel ideas for further development of thin film solar cells are also discussed towards the end of this paper.

This talk reviews our recent work on material growth, device fabrication and application of terahertz quantum cascade lasers (THz QCLs).

Area-selective channel material growth for 2D transistors is more desirable for volume manufacturing than exfoliation or wet/dry transfer after large area growth. We demonstrate the first top-gate WS 2 p-channel field-effect transistors (p-FETs) fabricated on SiOx/Si substrate using channel area-selective CVD growth. Smooth and uniform WS 2 comprising approximately 6 layers was formed by area-selective CVD growth in which a patterned tungsten-source/drain served as the seed for WS 2 growth. For a 40 nm gate length transistor, the device has impressive electrical characteristics: on/off ratio of ~106, a S.S. of ~97 mV/dec., and nearly zero DIBL.

Silicon bulk lifetime degradation in III-V material growth chambers has been a major hindrance to the development of III-V/Si tandem solar cells. While the exact mechanisms responsible for this degradation remain unknown, many researchers have attributed such degradation to extrinsic contaminants that diffuse into silicon bulk during growth. In this work, we show that thermal activation of grown-in defects in float zone wafers is also a key mechanism behind such degradation. Annealing of the wafer at 1000 °C to remove these defects, together with a SiN X diffuse barrier layer deposition are both required to preserve the silicon bulk lifetime.

Three-dimensionally confined semiconductor quantum dots have emerged to be a versatile material system with unique physical properties for a wide range of device applications. With the advances in nanotechnology and material growth techniques for both epitaxial and colloidal quantum dots, recently the research has been shifted largely towards quantum dot based devices for practical applications. In this short review, we have tried to assemble a selection of recent advances in the areas of quantum dots for computing and communications, solid state lighting, photovoltaics, and biomedical applications that highlight the state of the art.

We investigate the possibility that capitalist economies – those that industrialized first and the whole OECD group - may be reaching the growth plateau naturally, in a similar way to other complex systems in nature. In the system model of autocatalytic growth we introduce a set of endogenous and exogenous variables that provide negative feedbacks to material growth and push the economic system into the mature stage of development. Based on general developmental stages for dissipative systems, we identify variables that would uniquely mark the transition to maturity: p.c. energy consumption, GDP and energy consumption distribution, and sector composition of labor and GDP. Empirical findings suggest that the observed groups of capitalist countries may have terminated their historic phase of intensive economic growth and are entering the mature stage. This provides a tentative explanation of the observed slow-down of long-run rates of GDP growth in the G7 economies and in Western Europe.

We report on the improvement of propagation loss in Ge-on-SOI waveguides developed for mid-infrared wavelengths. Strip waveguides of varying widths have been developed in 0.85 μm thick Ge core and an improvement of up to ~3.5 dB/cm has been achieved by annealing the samples at 700 °C for 120 s. The improvement is consistent for both TE and TM polarized light at 3.682 μm. The method is proven feasible for repairing material growth defects and achieving loss performance commensurate with that required for integrated photonics for sensing applications. The minimum propagation loss achieved is ~10 dB/cm after annealing.

We investigate experimentally and theoretically the band structure of the (In0.53Ga0.47As)1−z (In0.52Al0.48As) z digital alloy grown by using molecular beam epitaxy as a function of z, where z is defined by the thickness fraction of the InGaAs and the InAlAs layers lattice-matched to InP. To calculate the band structures of the InGaAs/InAlAs digital alloy, we used the 4 × 4 k·p method; then, we compared these band structures with the photoluminescence experimental results. These experimental and theoretical results show that the InGaAs/InAlAs digital alloy not only can contribute to the method of band-gap engineering by using various types of thickness combinations but also can cover the wavelength gap of 1.2 μm (1.1 μm (GaAs) < λ < 1.3 μm (InP)), that only the quantum dot can cover. We also propose a quantum-well structure that is able to cover the wavelength gap.

Photon management is essential in improving the performances of optoelectronic devices including light emitting diodes, solar cells and photo detectors. Beyond the advances in material growth and device structure design, photon management via nanoscaled phenomena have also been demonstrated as a promising way for further modifying/improving the device performance. The accomplishments achieved by photon management via nanoscaled phenomena include strain-induced polarization field management, crystal quality improvement, light extraction/harvesting enhancement, radiation pattern control, and spectrum management. In this review, we summarize recent development, challenges and underlying physics of photon management in GaN-based light emitting diodes and solar cells.

In this paper, the Chemical Beam Epitaxy approach to GaAsN material growth has been investigated. Photoluminescence and Hall effect measurements were performed to clarify the influence of defects on the transport properties, those of holes in particular. The PL intensity of near-band emission (1.35 eV-peak) for GaAs0.996N0.004 at low temperature ( 1) indicated that the N atoms were alloyed in a disordered arrangement. As a result, the corresponding alloy scattering mechanism was enhanced, contributing to the hole mobility decrease. However, compared to p-type GaAsN grown by MBE or MOCVD, our CBE-grown GaAsN showed a higher value of hole mobility.

In this study, we investigated the material growth and the local compositional homogeneity of CIGS thin films selenized from elemental Cu, In, Cu, Ga, and Cu stacked layers prepared by sequential electrodeposition, which is considered to be a promising production method for large-area thin film solar cells. It showed that the stacked layers first formed mixed metallic phases after a pre-heat treatment at 150 °C in vacuum. Several intermediate phases such as CuInSe2, CuInrichGapoorSe2, Cu2Se, InSe/In2Se3, CuGa2, and CuInpoorGarich formed in Se vapor at a lower temperature (e.g.

Thermocapillary convection is an important content in the study of microgravity fluid physics. It is not only the problem of fluid physics mechanism such as convection stability, but also closely related to spacecraft flow control, efficient heat transfer, etc., and has direct guiding significance for material growth processes such as floating zone method and Czochralski method. This chapter mainly introduces the research status of thermocapillary convection about an annular liquid pool, the scientific experiment and partial analysis results carried out by the project group in the early stage, and the development of space experimental payload, space experiment and preliminary experimental results about the annular liquid pool from SJ-10 mission.

The premises and conclusions of the Science and the Future conference held in 2013 are the basis for this paper. I shall describe the changes occurred in the world since 2013 to present both on the positive and on the negative side, together with the failures to change, that will be discussed during the present conference. I shall especially point out the failure to address the contradiction between material growth and sustainability. The limit posed by the growing complexity of the global economy will be demonstrated, showing its implications for theungovernability of the system. I will stress the difficulty and urgency of a fully rational analysis and the discussion of some strongholds of the present social paradigm, which are intrinsically entangled with human and material unsustainability.